These two have a rough start of because of how young the heroine is and culture clash. I liked the fact that Margot wasn't blinded by insta-lust and just because she found Arran attractive she didn’t instantly trust him and it didn’t solve all their problems. Margot's just too young, too scared, and too bitter about not being able to marry someone remotely of her choosing and she ends up leaving Arran after only a couple months of marriage. Even though there is initial chemistry, these two have to work at it and I enjoyed every emotional high and low they provided.

2. Amani and Jin - Rebel of the Sands by Alwyn HamiltonJin grabbed my wrist
before my knuckles could get flirting distance from his nose. He pulled me into
him, knocking me off balance. “Here’s a tip for you.”He was close to me now,
close as he had been when he kissed me, or when I kissed him. “Don’t try to hit
a man in the face when he’s looking straight into your eyes. You’ve got traitor
eyes, Bandit.”

I drove my other fist
into his gut hard enough that my knuckles popped. Jin doubled over, coughing.
“Thanks for the tip.”I wished victory didn’t feel so much like I’d sprained my
hand.

"Any time.”He
clutched his stomach where I’d hit him, but it looked like he was laughing.

These two might not quite be considered a couple but I'm shipping looking into the future :) This is young adult, so the relationship developing between Amani and Jin is innocent enough but they still had some good heat and tension between them.

3. Benedict and Charlotte - Fortune Favors the Wicked by Theresa Romain“They slipped briskly into an intimacy from which they never recovered.”-F. Scott FitzgeraldI was blown away with how emotionally engaging Benedict and Charlotte were. Quite frankly, I could sit and listen to this couple read the phone book to each other. I savored their sexual teasing, humor, friendship, and love that radiated from their conversations. Benedict and Charlotte made the book for me.

4. Dee and Lucas - Angel Creek by Linda HowardHe felt like banging his head against the wall in frustration, and then suddenly he laughed, because he hoped she would be driving him crazy like that for the rest of his life. Maybe he was already crazy, because he could swear he'd seen a glint of amusement in those witch-green eyes. She loved making him lose control.The way Lucas was attracted to Dee's personality made my face hurt from grinning. These two were such cats on a hot tin roof. They bicker and straight up fight but there was also a thread of exasperation that leaned toward humor, teasing, and affection that saved it from feeling mean or hateful.

5. Joe and Caroline - MacKenzie's Mission by Linda Howard
A mixture of Rhett and Scarlet with the couple from The Notebook, yeah, I couldn't leave this couple off the list.

6. Gerrit and Anna - The Dutch Girl by Donna ThorlundThe romance between Anna and Gerrit is not the full focus of this historical story but when they show up together on the pages, they spark. When we first see them together their conversation and back and forth had my toes curling, not so much because of sexual reasons but from two people attracted to each other whose intelligence, wit, and teasing caused heat.

7. John and Grace - To Win a Lady's Heart by Ingrid Hahn
The hero and heroine were both so beautifully awkward and I loved how different from the usual Regency couples they were.

8. Livvy and Nicholas - Hate to Want You by Alisha RaiTheir encounters were usually a haze of sweet and pleasure and filthy words and filthier actions.The first look at the couple is so filled with emotion and sexual tension, you'll be hooked. This couple has some pretty gritty, raw, and emotional sex scenes but I would argue what made them feel so raw was the deep emotional aspect between the two. Nicholas and Livvy's desire and love for one another is the stuff of Shakespearean plays.

9. Julian and Elizabeth - No Other Duke Will Do by Grace BurrowesThis was how it was supposed to be between a man and a woman, both comfortable and daring, a private adventure.Through their discussions we see Elizabeth testing Julian and Julian slowly coming alive as if Elizabeth is a shock to his system. As Elizabeth notes, Julian listens to her and their gentle teasing and probing one another made me sigh along in happiness.

10. Adam and Sarah - Once Upon a Christmas Eve by Elizabeth HoytHe broke their kiss and laid his forehead against hers. "Make me stop.""I can't," she whispered."Then we're doomed," he said, his voice husky and low. "For I'm unable to stop myself. I want you. Day and night and all the time in between. I want you."Our hero is able to keep himself rather emotionally contained, except when he gets around our heroine and then we get to see cracks form in the façade; I live for the cracks. Sarah was the perfect combination of stiff and melting when she was around d'Arque; I loved how she stepped up to d'Arque's challenging but also how she softened to his touch. They are the couple who give you shivers up and down your spine. They snap, spark, crash, and melt together in a way that make you want to reread their story as soon as you finish.Winner:Livvy and Nicholas

"You're not my secret anymore. My love for you is bigger than anyone who might try to tear us apart." He paused. "I won't leave you, Livvy. You don't have to trust me completely right now, but watch me. Watch me fight for you this time."Gah, this couple! The love, hurt, pain, laughter, emotion, and sex. The Sex, y'all. But also the Emotion, y'all. They made me live their ups and downs with them.